Pressure gauge



Jan. 9. 1951 H. ALLEN 2,537,729

PRESSURE GAUGE original Filed Nov. 26, 1940 2 sheets-shawl f fl, A

Jan. 9, 1951 H. ALLEN 2,537,729

PRESSURE GAUGE Original Filed Nov. 26, 1940 2 Sheets-Sheet 2 [NVE RPatented Jan. 9, 1951 PRESSURE GAUGE Herbert Allen, Houston,

cron Iron Works, Hous of Texas Tex., assignor to Camton, Tex., acorporation Original application November 26, 1940, Serial and thisapplication February 9, 1945, Serial No. 576,957

N0. 367,160. Divided 6 Claims. l

This application is a division or my prior co pending application SerialNo. 367.1%, led Non vember 26, 1940 for Pressure Gauge which maturedinto United States Letters Patent No. 2,369,650, issued February 2G,1945.

This invention relates to a pressure responsive assembly suitable foruse in pressure gauges and has for its general object the provision c-fa pressure responsive assembly having the frictionless characteristicsof a Bourdon tube type pressure responsive means with the desirableruggednees and power available in other types of gauges, such as pistongauges.

It is well known that a piston type of pressure responsive assembly ismore desirable from the standpoint of positive and powerful movementunder pressure than is a Bourdon tube type oi device, but that it isvery difcult if not impossible to pack a piston type pressure responsiveassembly without the introduction of frictic-nal or other resistancecharacteristics which substantially impair or destroy the desirablecharacteristics of the piston type assembly.

It` is, therefore, an object oi this invention to provide asubstantially fricticnless seal between the load member of an elasticsystem and a pressure gauge body.

Another object of this invention is to provide such a seal which will bedistorted a` minimum amount over a wide range of pressures being gauged.

Another object of this invention is to provide a means for sealing apressure gauge in which the weakest part of the sealing means issubstantially relieved of unbalanced forces tending to rupture it by ashearing action.

Another object of this invention is to provide a means for sealing amovable element of a pressure gauge positively against the escape ofliquid or other pressure fluid, while substantially eliminating anypossible modification of the action of the pressure gauge by thesealingmeans.

Other objects and advantages of this invention will become apparent fromthe following description taken in connection with the accompanyingdrawing in which is set forth by way of illustration one embodiment ofthe invention.

In the drawing:

Fig. 1 is a view partly in side elevation and par ly in vertical crosssection illustrating a pressure gauge constructed in accordance withthis invention.

Fig. 2 is a view similar to the lower portion oi Fig. 1 but showing theparts of the pressure gauge 2 in the position they occupy when the gaugeis subjected to substantial pressure.

Referring more in detail to the drawing, the I having a clamped withinas indicated at 9 whereby it maybe connected to the housing I, and therigid portion 1 is adapted te be secured against the shoulder Ill of thebase 8 with a gasket il interposed between the member 'I and theshoulder IIJ for the purpose of pro- Viding a seal between these parts.A seal is provided between the base 8 and the housing I at the upper endof the threaded section 9 by means of a sealing ring I2 of rubber or anyother suitable packing substance.

The rigid member l is providedwith a countersink in its lower Surfaceand with an opening through its central part, and an apertured iiexiblemember in the form of is disposed within vthis in place therein as wellas being sealed therein by clamping against the shoulder lil with thegasket II interposed between the shoulder I0` on an annular elastic diski4 nular elastic member or disk I4 is thus clamped about its outer edgeswhile its central portion is" left free to ex.

An opening I5 is formed through the central portion of this annularelastic member and in this lows or Sylphcn` the lower end of be securedeither II. It will be appreciated that this bellows or Slyphon mightwithin the opening itself or to one or the other face of the member I dadjacent tact the lower end of a pressure pin or rod` I9 forming a partof the elastic system 6 `of the indicator mechanism. This elastic systemis clearly apparent in Fig. 2 and countersink I3v and held .consists @iive;

3 relatively narrow flexible parts 2D extending upwardly from the upperend of the substantially rigid part I9 and merging at their upper endswith the upstanding arms 2I to form the posts 22. A linkage foractuating the indicator disk 4 is secured to the upper end of theseposts respectively by means of bolts or the like passed through openings23. The nature of this linkage forms no part of the present inventionand is therefore not illustrated, it being understood that any suitablemechanical linkage might be used for connecting these parts.

The base 8 is adapted for connection to a pressure vessel by means ofthreads 24 on its lower end.

In operation, the fluid under pressure is admitted to the space withinthe base 8 below the exible member It and within the Sylphon Il. It willbe seen that the flexible member I4 will flex under such pressure, itscentral portion about the opening I5 moving upwardly as seen in Fig. 2.At the same time, the force of the pressure within the base 8 will beexerted on the inner surface of the upper end of the Sylphon andtransmitted thereby directly to the movable element I9 of the elasticsystem of the gauge. The parts are preferably so designed that under thesame pressure, that portion of the element I4 about the opening I5 willilex substantially to the same extent that the part I9 will be moved.Thus, when pressure is exerted upon the parts illustrated, the part oithe element I4 to which the Sylphon is secured, and the part I9 of theelastic system 6 will move substantially tc the same extent and in thesame direction and there will be substantially no elongation or flexingof the Sylphon. This leaves the element I9 free to move withoutinterference and under no substantial innuence other than that exerted`by the pressure of the fluid being gauged. The Sylphon Il servessubstantially no other purpose than to provide a seal between themovable edge of the element I4 about the opening I5, and the movablepart I8 of the elastic system 6. While the Sylphon is illustrated asbeing closed at its upper end I8 it will be appreciated 'that any othersuitable arrangement might be employed which would result in the forcefrom the pressure exerted through the opening I5 being applied directlyto the end of the rigid bodily movable part or load rod IS. It willfurther be appreciated that since the pressure of the iluid istransmitted directly through the wall I8 at the upper end of the Sylphonto the part i9 of the elastic system 6, the pressure of the fluid willnot elongate the Sylphon and the Sylphon will as a matter of fact retainsubstantially the same length regardless of the pressure being gauged.For this reason the unbalanced stresses to which the Sylphon issubjected will be principally radial stresses tending to enlarge theSylphon, and against such stresses a Sylphon such as illustrated iscapable of very strong resistance.

In such a structure it will be seen that the bellows will move as a unitand will serve principally as a flexible seal between the ilexible orelastic annular element I4 and the elastic system 6, but in Such amanner that it will not be substantially flexed during use and willhence exert substantially no restraining or modifying influence upon themovement of the element IS under the pressure being gauged. y

It will thus be seen that a means has been ..-muss mmm au of the objectsand advanasemee tages set forth in connection with this invention havebeen attained.

Having described my invention, I claim:

l. In a pressure gauge, the combination of an apertured resilient meansfirmly held at its periphery, a load rod movable in response to pressureapplied thereto, said resilient means and load rod being so constructedand arranged as to be movable independently of each other but insubstantially equal amounts in the same direction in response to anygiven pressure, and a bellows having an open end secured to saidresilient means about said aperture therein and extending to and incontact with an end portion of said rod for providing a exible sealbetween said resilient means and said rod.

2. In a pressure gauge, a hollow body, an elastic means having aperipheral part anchored and sealed to said body, said elastic meanshaving an opening and one surface surrounding the opening exposed topressure within the body, a second elastic means having a part anchoredto said body and a part exposed to the force of the pressure throughsaid opening, exible sealing means secured to said first means aboutsaid opening and to said part exposed to pressure to seal between saidfirst means and the last mentioned part of said second means, said twoelastic means responsive in the same degree to pressure whereby thecondition of the sealing means is not substantially altered by pressurevariations, and ndicating means operatively connected to said secondelastic means for indicating flexure thereof.

3. In a pressure gauge, the combination of a housing having a passage,an elastic closure for said passage and subject on one side to thepressure to be gauged and having an opening therethrough, an elasticsystem on the opposite side of said closure including a bodily movablepart responsive to the pressure, said elastic closure and elastic systembeing of such design that the portion of said elastic closure about saidopening will move substantially the same amount as the bodily movablepart of said elastic system upon the application of pressure, and allexible sealing means sealed to said elastic closure about said openingand connected to the bodily movable part to form a exible seal betweensaid elastic closure and said bodily movable part, the latter being`exposed to the force of the pressure within the sealing means andclosure.

4. In a pressure indicator of the type having a load pin disposed in thepassage of a gauge body, said pin movable in response to pressure andoperably connected to a pressure indicator the improvement which residesin a seal for the load pin comprising an apertured elastic membersecured and sealed at its outer periphery to the gauge body, said memberadapted to respond to pressure so that a part thereof will move inresponse to pressure at substantially the same rate and direction asdoes the load pin, and a flexible sealing means between said part of theapertured member and the load pin completing closure of the passagewhereby free movement of the load pin in the passage in response topressure is provided.

5. A seal adaptable for use in conjunction with the load pin of theelastic system of a pressure gauge disposed in the passage of a gaugebody comprising an elastic apertured member disposed in the passage andhaving its outer periphery secured and sealed to the gauge body, abellows connected between the end of the load pin and the elastic memberadjacent the aperture to com.

5 plete the closure of the passage, said elastic inember, elastic systemand load pin being so related that the connection of the bellows to themember is moved in response to pressure substantially the same amount asis the end of the load pin whereby the bellows does not substantiallyaect the movement of the load pin.

6. In a pressure gauge, an elastic system including a bodily movablepart responsive to the force kof the pressure to be gauged to be movedthereby and flex said system, means directing the application ofpressure to the bodily movable part,- said means including a bellowswith a. portion engaging said part and' adapted to move therewith, aiiexible sealing member secured to the bellows remote from said elasticsystem and with said bellows forming a flexible wall to serve as' partof the means for retaining the pressure to be gauged, said ilexiblesealing member and bode ily movable part being so constructed andarranged as to be movable independently of each other but substantiallyequal amounts in the same direction in response to any given pressure,and means responsive to movable part for indicating flexure of saidelastic system.

HERBERT ALLEN.

REFERENCES CITED The following references are of record in the leof thispatent:

' UNITED STATES PATENTS Number Name Date 15,624 Shaler Aug. 26, 185616,428 Allen June 20, 1857 1,391,077 Richter Sept. 20, 1921 1,406,616Cutts Feb. 14, 1922 1,761,130 Kennedy June 3,1930 1,859,089 Holmes May17, 1932 2,297,679 Allen Oct. 6, 1942 movement of said bodily

